kernel-fxtec-pro1x/arch/arm/nwfpe/fpa11.h
Lennert Buytenhek bedf142b8b [ARM] 3118/1: fix and reenable nwfpe extended precision emulation for big-endian
Patch from Lennert Buytenhek

nwfpe extended precision emulation used to be broken on big-endian
and was therefore disabled.  This patch fixes nwfpe so that it copies
extended precision floats to/from userspace in the proper word order
(similar to patch #2046, see the description of that patch for an
explanation) and reenables the Kconfig option.

Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-11-07 21:12:08 +00:00

118 lines
3.7 KiB
C

/*
NetWinder Floating Point Emulator
(c) Rebel.com, 1998-1999
Direct questions, comments to Scott Bambrough <scottb@netwinder.org>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#ifndef __FPA11_H__
#define __FPA11_H__
#define GET_FPA11() ((FPA11 *)(&current_thread_info()->fpstate))
/*
* The processes registers are always at the very top of the 8K
* stack+task struct. Use the same method as 'current' uses to
* reach them.
*/
#define GET_USERREG() ((struct pt_regs *)(THREAD_START_SP + (unsigned long)current_thread_info()) - 1)
#include <linux/config.h>
#include <linux/thread_info.h>
/* includes */
#include "fpsr.h" /* FP control and status register definitions */
#include "milieu.h"
struct roundingData {
int8 mode;
int8 precision;
signed char exception;
};
#include "softfloat.h"
#define typeNone 0x00
#define typeSingle 0x01
#define typeDouble 0x02
#define typeExtended 0x03
/*
* This must be no more and no less than 12 bytes.
*/
typedef union tagFPREG {
float32 fSingle;
float64 fDouble;
#ifdef CONFIG_FPE_NWFPE_XP
floatx80 fExtended;
#else
u32 padding[3];
#endif
} FPREG;
/*
* FPA11 device model.
*
* This structure is exported to user space. Do not re-order.
* Only add new stuff to the end, and do not change the size of
* any element. Elements of this structure are used by user
* space, and must match struct user_fp in include/asm-arm/user.h.
* We include the byte offsets below for documentation purposes.
*
* The size of this structure and FPREG are checked by fpmodule.c
* on initialisation. If the rules have been broken, NWFPE will
* not initialise.
*/
typedef struct tagFPA11 {
/* 0 */ FPREG fpreg[8]; /* 8 floating point registers */
/* 96 */ FPSR fpsr; /* floating point status register */
/* 100 */ FPCR fpcr; /* floating point control register */
/* 104 */ unsigned char fType[8]; /* type of floating point value held in
floating point registers. One of
none, single, double or extended. */
/* 112 */ int initflag; /* this is special. The kernel guarantees
to set it to 0 when a thread is launched,
so we can use it to detect whether this
instance of the emulator needs to be
initialised. */
} FPA11;
extern int8 SetRoundingMode(const unsigned int);
extern int8 SetRoundingPrecision(const unsigned int);
extern void nwfpe_init_fpa(union fp_state *fp);
extern unsigned int EmulateAll(unsigned int opcode);
extern unsigned int EmulateCPDT(const unsigned int opcode);
extern unsigned int EmulateCPDO(const unsigned int opcode);
extern unsigned int EmulateCPRT(const unsigned int opcode);
/* fpa11_cpdt.c */
extern unsigned int PerformLDF(const unsigned int opcode);
extern unsigned int PerformSTF(const unsigned int opcode);
extern unsigned int PerformLFM(const unsigned int opcode);
extern unsigned int PerformSFM(const unsigned int opcode);
/* single_cpdo.c */
extern unsigned int SingleCPDO(struct roundingData *roundData,
const unsigned int opcode, FPREG * rFd);
/* double_cpdo.c */
extern unsigned int DoubleCPDO(struct roundingData *roundData,
const unsigned int opcode, FPREG * rFd);
#endif